We now have an ABC news investigation. Into a shadowy and cruel world. Right now 28 million people -- children across the globe are forced to work long hours at low wages. And ABC's Bob Woodruff traveled all the way to India for our new series Woodruff explorers. The show us the little boys as young as nine force deep underground to do one of the most dangerous jobs on earth. 28. Welcome to the rat holes of northeast India I can barely and and dark and confusing maze of coal mine. -- hundreds of feet underground. Come here with -- -- a teenager who's been working in these tunnels since he was twelve. He just won the thousands of children small in the desperate enough at a place where child labor laws are all but ignored. Behind on me just -- -- being. Yeah. There is a history of earthquakes here. Collapsed tunnels -- trapping workers -- has blasted -- the only guy big knock. Look at none of the morning. Yeah. -- window has been working to end this kind of child labor was the youngest. Child he's ever known about that worked in the -- -- Nine years old parts and. Did you say he has seen accidents. The -- collapsing fielded some degree what he did you have survived. That there is as as -- and then -- him. The -- and it's in. -- this work has been banned in India since 1952. It's up to each state to enforce the law -- authority is easily -- Campbell has never been to school you are just to feed himself yes never seen in. -- outside. This place. This he looks -- -- -- just six days a week ahead in the school before his baby brother did keep Bemba has a new dream. The mother no walks -- two miles each day to discriminate. -- gathers together six dollars a month to pay the tuition as it did he will never seem like that he had. Bob Woodruff ABC news in northeast intact and I think. More Bob's report from our new series what if explores later tonight on Nightline.

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